CVE-2026-126408
Wasmtime 47.0.0 before 48.0.8 Denial of Service via TypedFunc Type-Check Panic
CVSS Score
1.8
EPSS Score
0.0%
EPSS Percentile
0th
Wasmtime 47.0.0 before 48.0.8, 49.0.0 before 49.0.5, and 50.0.0 before 50.0.1 contains an insufficient type-check in the TypedFunc embedder API for I31, Option<I31>, and Option<NoneRef> parameter or result types, reaching an unreachable!() path. A malicious guest module exporting a function that uses another anyref-hierarchy type can panic the host embedding, causing denial of service.
| CWE | CWE-617 |
| Vendor | bytecodealliance |
| Product | wasmtime |
| Published | Nov 13, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:A/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:L Attack Vector
Adjacent
Attack Complexity
High
Privileges Required
High
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low
Affected Versions
bytecodealliance / wasmtime
47.0.0 < 48.0.8
bytecodealliance / wasmtime
49.0.0 < 49.0.5
bytecodealliance / wasmtime
50.0.0 < 50.0.1